Ask HN: To Patent, or Not To Patent

We filed for a provisional patent a year ago, and the year is just about up, so we need to decide whether to go for the full patent. Our lawyer is saying $5k for an opinion of counsel and then up to $10k more for the full patent. This is basically all of our remaining capital and then some. The patent, if we get it (82% were rejected last year), would theoretically protect us from competition if we could afford to litigate. More likely it would serve as a reason for us to get bought. If we don't go for the patent we won't have protection (not that it would come in for 3+ yrs or whatever), but we could still try and rule the market we are in. A patent might also help us get funding, if we try and seek it (more funding, right now we've got friends and family money). Needless to say, spending the rest of our money would put us in a tight spot.

Just wondering what HN's denizens thought of our situation or patents in general. thx.